is it true that Different atoms of an element have the same number of protons.

Answer:

60.8%

Explanation:

We'll begin obtaining the molar mass of cobalt(II) fluoride, CoF2. This can be done as shown below:

Molar mass of CoF2 = 59 + (19x2) = 97g/mol.

The percentage composition of cobalt in cobalt(II) fluoride, CoF2 is given by:

Mass of Co/Molar Mass of CoF2 x 100

=> 59/97 x 100 = 60.8%

Therefore, the percentage composition of cobalt in cobalt(II) fluoride, CoF2 is 60.8%

Hey

Matter can neither be created nor destroyed.

Explanation:

This is the law of conservation of matter (mass). One can prove this by performing a simple experiment at home.

Have a great day

Answer:

b.

Explanation:

Americium decays to neptunium 237.

An alpha particle has 2 protons and 2 neutrons, so 4 helium atoms.

241-4=237

Answer:1.08

Explanation:

Answer:

1.08kg/cm^2

Explanation:

Edge2021

Answer:

M=0.15

Explanation:

138 g AgNO -> 1 mol AgNO

10 g AgNO   -> x

x= (10 g AgNO * 1 mol AgNO)/138 g        x=0.07 mol AgNO

450 mL=0.45 L

M= mol solute/L solution

M= 0.07 mol AgNO/0.45L

M=0.15

Answer:

The combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy

Explanation:

Given;

CH₄ + 2O₂ → CO₂ + 2H₂O, ΔH = -890 kJ/mol

From the combustion reaction above, it can be observed that;

1 mole of methane (CH₄) released 890 kilojoules of energy.

Now, we convert 59.7 grams of methane to moles

CH₄ = 12 + (1x4) = 16 g/mol

59.7 g of CH₄ [tex]= \frac{59.7}{16} = 3.73125 \ moles[/tex]

1 mole of methane (CH₄) released 890 kilojoules of energy

3.73125 moles of methane (CH₄) will release ?

= 3.73125 moles x  -890 kJ/mol

= -3320.81 kJ

Therefore, the combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy

Answer:

The combustion will release -3,321 KJ/mol of energy

Explanation:

Answer:

the liver

Explanation:

it processes alcohol, work very hard

Answer:

5) You push hard on a heavy desk and try to move it. You do work on the desk: A.- Whether you move it or not, as long as you exert a force. B.- Only if the desktop moves. C.- Only if the desktop does not move. D.- Never; the desk does work on you. E.- None of the above. CAN YOU HELP ME?

B.- Only if the desktop moves.

Explanation:

No work is done if a force is exerted but no displacement occurs. A force perpendicular to the displacement does no generate work.

Answer:

b

Explanation:

Answer:

Here's what I get  

Explanation:

1. Nitrogen

A nitrogen atom has a central positively-charged nucleus surrounded by seven electrons. Two are in the first energy level and the other five are in the second.

2. Sodium

In a sodium atom 11 electrons surround the nucleus in three energy levels in a 2-8-1 order.

3. Calcium

In a calcium atom 20 electrons surround the nucleus. The electron shell configuration  is 2-8-8-2.  

4. Bromine

The Bohr model of a bromine atom would show 35 electrons surround the nucleus in a  is 2-8-8-17 shell configuration.  

More modern variations use principal quantum numbers and a 2-8-18-7 arrangement.

5. Neon

A neon atom has 10 electrons surrounding the nucleus in a 2-8 shell configuration.  

Answer:

A system absorbs more energy than it releases and has a positive AH  

Explanation:

Answer:

Explanation:

Endothermic (endo = into + thermic = heat) means that heat energy is going into a system.

The products will have more energy than the reactants and ΔH will be positive.

A is wrong, because ΔH is positive.

C and D are wrong, because the system absorbs more energy than it releases.

Answer:

The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Aluminium, or 26.981538 grams.

Answer:

A) 12 mol H2O.

Explanation:

Hello,

In this case, for the given reaction:

[tex]2C_2H_6+7O_2\rightarrow 4CO_2 + 6 H_2O[/tex]

We notice that oxygen is in a 7:6 molar relationship with water, for that reason, the resulting moles of water turn out:

[tex]n_{H_2O}=14molO_2*\frac{6molH_2O}{7molO_2} \\\\n_{H_2O}=12molH_2O[/tex]

Thus, the answer is A) 12 mol H2O.

Best regards.

Answer:

carcinogen

Explanation:

cigarette smoke and UV radiation both of the capability to cause cancer cells in living tissue, meaning they can both be classed as carcinogens

Answer:

nonpolar

Explanation:

Use the phrase "like dissolves like"

- Hope that helps! Please let me know if you need further explanation.

Answer:

36 grams as 1 mole is 12 grams

Answer:

tbh idk cause I will love to answer your question but ehh

Answer:

The mass of K₂Cr₂O₇ needed to create a saturated solution in 400 grams of water at 50°C is 120 grams

Explanation:

To answer the question, we will be required to know the solubility of potassium dichromate, K₂Cr₂O₇ in H₂O at 50°C

From the solubility curve, we have, 30 g of K₂Cr₂O₇ will be required to create a saturated solution in 100 g of at 50°C. Therefore, the amount of K₂Cr₂O₇ that will be required to create a saturated solution in 400 g of water, is given by the following equation;

[tex]400 \times \frac{30 \, g \ K_2Cr_2O_7}{100g \ H_2O} = 120 \, g[/tex]

Therefore, the mass of K₂Cr₂O₇ needed to create a saturated solution in 400 grams of water at 50°C = 120 grams.

Answer:

Approximately 128 g of K₂Cr₂O₇ will saturate 400 g of water.

Explanation:

From Literature and solubility curves, the solubility of K₂Cr₂O₇ at 50°C was obtained to be approximately 32 g/100 mL.

Solubility of K₂Cr₂O₇ in water at 50°C = 32 g/100 mL of water

So, how much K₂Cr₂O₇ will dissolve in 400 g of water?

Density of water = 1 g/mL

So, 1 g of water = 1 mL of water

400 g of water = 400 mL of water.

So, if 100 mL of water dissolves 32 g of K₂Cr₂O₇

400 mL of water will dissolve (32 × 4) g of K₂Cr₂O₇, that is, 128 g of K₂Cr₂O₇.

Hope this Helps!!!!

Answer:

Astronomers have observed their movements over time

Explanation:

Just took the test!!!

The future collision of Andromeda and milky way are known by astronomers because ; ( C ) Astronomers have observed their movements over time

Andromeda also known as messier 31 is a spiral galaxy that appears as a  milky blur when viewed from the earth and it is believed to be slightly over 2.5 million years old.

Astronomers predict that based on its movement and the movement of the Milky way there is most likely going to be a collision in future between the Andromeda and milky way.

Hence we can conclude that The future collision of Andromeda and milky way are known by astronomers because Astronomers have observed their movements over time

Learn more : https://brainly.com/question/2849133

Answer:

biosphere

Explanation:

The carbon cycle is the biogeochemical cycle by which carbon is exchanged between the biosphere, geosphere, hydrosphere and atmosphere of the Earth.

The biosphere refers to the regions of the surface and atmosphere of the earth or another planet occupied by living organisms.

Plants are responsible for taking in carbon in nature. When more trees are planted, carbon is absorbed by plants which is a component of the biosphere. Hence planting more trees means increasing the intake of carbon into the biosphere.

Answer:

D

Explanation:

Answer:

For 2. the answer is 15.0 mL

For other examples, you can solve by exact way as I have solved the 2nd example.

I have writen down all the balanced chemical reaction equation for examples 1, 3, 4, 5 for you. ( picture 2 )

Explanation:

Please see the step-by-step solution in the picture attached below.(picture 1)

Hope this answer can help you. Have a nice day!

Answer:

It uses the mass and specific heat of water along with a thermometer to measure the gain or loss of energy when a substance is added.

Explanation:

The calorimeter is an instrumental device, which is used to measure the heat of chemical reactions. The heat is measured when the reactants change their state in specified conditions.

The correct answer is:

Option D. It uses the mass and specific heat of water along with a thermometer to measure the gain or loss of energy when a substance is added.

The coffee cup calorimeter works as:

1. Coffee cup is a type of insulator. The cup of styrofoam with an inserted thermometer can calculate the heat transfer.

2. The thermometer is used to measure the change in the enthalpy of the reaction.

3. The water in the cup absorbs the heat from a reaction, and the cup is adiabatic. Thus, the outer cup is an insulator.

4. The coffee cup measures the specific heat and mass of the water during a chemical change.

Thus, the coffee cup calorimeter uses the heat transfer and mass of the water when a substance is added.

To know more about calorimeter, refer to the following link:

https://brainly.com/question/10987564

both

Explanation:

an ecosystem is the environment they live in which includes other living things

Answer:

3. both of the above

Explanation:

Living things interact with each other. Suppose you have a pond. It is an ecosystem. The fish in the pond interact with each other, and may even interact with other species like frogs or insect by eating them or living peacefully with them. Living things also interact with their environment such as fishes or some organisms might interact with the plants, logs, the available sunlight, all sorts of these factors which make up the environment.

Thus organisms within an ecosystem interact with each other and their environment.

Answer:

220g of CO2

Explanation:

Step 1:

The balanced equation for the reaction.

2C5H11OH + 15O2 —> 10CO2 + 12H2O

Step 2:

Determination of the number of mole of CO2 produced by burning 1 mole of C5H11OH.

From the balanced equation above,

2 moles of C5H11OH produced 10 moles CO2.

Therefore, 1 mole of C5H11OH will produce = (1 x 10)/2 = 5 moles of CO2.

Therefore, 5 moles of CO2 is produced from the reaction.

Step 3:

Conversion of 5 moles of CO2 to grams.

Molar mass of CO2 = 12 + (2x16) = 44g/mol

Number of mole of CO2 = 5 moles

Mass of CO2 =...?

Mass = mole x molar mass

Mass of CO2 = 5 x 44

Mass of CO2 = 220g.

Therefore, 220g of CO2 were obtained from the reaction.

Answer:

the ability to be reproduced or copied.

Explanation:

Answer:  the ability of an entire experiment or study to be reproduced, either by the researcher or by someone else working independently.

Answer: A. They show the oxidation and reduction halves of a reaction.

Explanation:

Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.

For a redox reaction: [tex]A+B^+\rightarrow A^++B[/tex]

Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.

oxidation half at anode : [tex]A\rightarrow A^++e^-[/tex]

Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.

reduction half at cathode:  [tex]B^++e^-\rightarrow B[/tex]

Half-reactions show the oxidation and reduction halves of a reaction. The correct answer is option A.

Oxidation is a chemical reaction that involves the loss of electrons by a molecule, atom, or ion. This process results in an increase in the oxidation state of the species undergoing oxidation.

Half-reactions are used to show the oxidation and reduction half of the reaction separately, which makes it easier to balance the overall reaction and to identify the species that are being oxidized and reduced.

In conclusion, half-reactions are used to show the oxidation and reduction halves of a redox reaction separately. Option A is the correct answer.

Learn more about oxidation here:

https://brainly.com/question/13182308

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Answer:

4NO + 6H2O = 4NH3 + 5O2

Explanation:

Think about it this way: there are 4N's 4O's and 12H's and 10O's on both sides that's what makes it balanced

Hope this helps :)

Answer:

An antioxidant helps in the mopping up and elimination of free radicals and a common example is Glutathione. Oxidation reactions Involves the transfer of electrons or addition of oxygen to a substance.

Antioxidants help in decreasing or prevention of the oxidation of the molecules due to free radicals being formed which causes damage in the cells of animals.

Answer:

no, not all objects emit electromagnet waves.

Explanation: because lets say the object is carpet it has no magnetic waves in it so not all objects do.